Magnetic head slider having ultra thin base layer with group 6a element and protective layer
Inactive Publication Date: 2010-12-02
SAE MAGNETICS (HK) LTD
View PDF1 Cites 2 Cited by
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Benefits of technology
[0009]In view of the above-described circumstances, an object of the present invention is to provide a magnetic head slider that is capable of reducing the total film thickness of the seed layer and the protective film while securing robustness against corrosion.
[0011]Pin holes are generated and develop with time due to corrosion even if they are not formed at the time of forming the seed layer and the protective film. Corrosion becomes a problem only when the pin holes penetrate through the protective film, as well as the seed layer, to reach the write head element and the read head element. Therefore, even if pin holes are formed in the protective film, there is no substantial problem when forming of the pin holes stops in the seed layer. Because of the effect of the 6A group element in improving robustness against corrosion of the seed layer that is mainly formed of silicon, pin holes which may reach the write head element and the read head element are less apt to occur even if the film thickness of the seed layer is reduced. This effect can be obtained by including at least 2 atomic fractions of the 6A group element in the seed layer. However, since the seed layer also functions as a bonding layer for the protective film, too high proportion of the 6A group element may decrease the adhesive property of the seed layer. The desired adhesive property of the seed layer can be ensured by setting the concentration of the 6A group element at 30 atomic fractions or less.
[0012]By the way, the seed layer is ordinarily subject to film stress caused by the wedge effect that is produced in the seed layer at the time of film formation. “The wedge effect” refers to a phenomenon, in which when a thin film is formed, particles (ions, atoms or clusters) that form the thin film are spattered toward a substrate (a slider body) and are then driven into and deposited on the substrate. Due to the wedge effect, stress remains in the thin film that is formed. The film stress tends to separate the seed layer from the slider body and actually separates the seed layer depending on the balance between the adhesive force and the separating force that are both caused between the seed layer and the slider body. Since the film stress is proportional to the film thickness, separation of the seed layer can occur more easily when the film thickness of the seed layer is increased. Separation of the seed layer exposes the slider body at the location where the separation occurs and may cause corrosion of the write head element or the read head element if they exist at the location. Adhesive property of the seed layer can be ensured to some extent by setting the concentration of the 6A group element at 30 atomic fractions or less. However, even in this case, if the film thickness is too large, then the separating force caused by the film stress may be larger than the adhesive force and separation may occur easily. It is therefore necessary to adjust both the concentration of the 6A group element and the film thickness of the seed layer in order to prevent corrosion. By setting the concentration of the 6A group element at 30 atomic fractions or less and by setting the film thickness of the seed layer at less than 1 nm, desired adhesive property of the seed layer can be achieved and film stress can be limited within a suitable range. Thus, corrosion resulting from separation of the seed layer can be simultaneously prevented. The reason why a film thickness of less than 1 nm can be achieved while preventing the formation of pin holes is that the concentration of the 6A group element is set at 2 atomic fractions or more to improve robustness against corrosion of the seed layer. The film thickness of the seed layer that is less than 1 nm is not only an effect of the present invention but also a requirement for solving the problem. Thus, the concentration of the 6A group element and the film thickness of the seed layer are related to each other, and both a reduction in film thickness and prevention of corrosion can be simultaneously achieved only when all of these requirements are satisfied.
Problems solved by technology
Corrosion becomes a problem only when the pin holes penetrate through the protective film, as well as the seed layer, to reach the write head element and the read head element.
However, since the seed layer also functions as a bonding layer for the protective film, too high proportion of the 6A group element may decrease the adhesive property of the seed layer.
Separation of the seed layer exposes the slider body at the location where the separation occurs and may cause corrosion of the write head element or the read head element if they exist at the location.
However, even in this case, if the film thickness is too large, then the separating force caused by the film stress may be larger than the adhesive force and separation may occur easily.
Method used
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View moreImage
Smart Image Click on the blue labels to locate them in the text.
Smart ImageViewing Examples
Examples
Experimental program
Comparison scheme
Effect test
examples
[0044]In the examples described below, the advantages of the present invention were confirmed by changing the composition and the film thickness of the seed layer and the film thickness of the protective film as parameters, and a suitable numeric range of each parameter was examined. Multi Deposition System MR3, a product from Shimadzu Corporation, was used to form the seed layer and the protective film. The system is capable of performing IBE, sputtering and FCVA. First, the surface of the lapped row bar was etched by means of IBE so that the PTR was adjusted into a desired shape. Adjustment of the PTR was performed by controlling, for example, the angle and power of ion beam. Next, the seed layer was formed by using a target of Si or the like. A predetermined amount of Ar gas was introduced into the sputtering chamber, and RF or pulsating DC was applied to cause discharge, thereby the seed layer having a desired thickness was formed. Thereafter, the protective film made of DLC was...
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More PUM
Login to View More Abstract
A magnetic head slider according to the present invention comprises: a slider body including either a write head element or a read head element or both the write head element and the read head element; a seed layer provided on an air bearing surface of the slider body, the seed layer covering either the write head element or the read head element or both the write head element and the read head element, the seed layer having a film thickness that is less than 1 nm; and a protective film formed of diamond-like carbon, the protective film covering the seed layer. The seed layer is mainly formed of silicon and contains a 6A group element in a proportion of 2 atomic fractions or more and 30 atomic fractions or less.
Description
BACKGROUND OF THE INVENTION[0001]1. Field of the Invention[0002]The present invention relates to a magnetic head slider, and more particularly to the construction of a protective film and a seed layer for the protective film formed on an air bearing surface.[0003]2. Description of the Related Art[0004]In a hard disk drive (HDD), data are read from a recording medium (a hard disk or a magnetic disk) and are written to a recording medium while a magnetic head slider (hereinafter referred to as a slider) glides over the recording medium with a small gap.[0005]A slider that reads data from the recording medium and that writes data to the recording medium is required to be free from corrosion in various environmental conditions, and is also required to be protected from collision against the recording medium. For this purpose, a protective film formed of diamond-like carbon (DLC) is formed on a surface of a slider body that is opposite to the recording medium, i.e., the air bearing surfa...
Claims
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More Application Information
Patent Timeline
Login to View More IPC IPC(8): G11B5/60
CPCG11B5/102G11B5/3106G11B5/40G11B5/6005
InventorYAMADA, TAIKIUEDA, KUNIHIRO
OwnerSAE MAGNETICS (HK) LTD